An Exhaust Gas Recirculation (EGR) control is a control system for reducing NOx of exhaust gas. A passage is provided for recirculating exhaust gas between an exhaust manifold and a downflow portion of a throttle valve of an intake manifold. An EGR valve or a flow control valve for regulating the proper volume of the recirculating gas is provided on the passage.
In general, an intake manifold is made from aluminum casting. Also, the EGR valve is made from aluminum casting. That results in heavy weight of the engine, thereby causing the rate of fuel consumption to be increased.
To solve the problem, a metal intake manifold was substituted with a plastic intake manifold in a conventional technique. However, as shown in FIG. 5, since EGR adapter 20P having EGR valve 210P contacts with a frame 10P of an intake manifold made from a plastic material, and the heat of the high temperature exhaust gas is directly transferred to the plastic frame 10P, the intake manifold seems to deform or deteriorate within its mechanical character.
Further, to solve the problem an exhaust gas passage is installed by being detoured near an outside of the cylinder head. However, various parts can not be installed near the high temperature exhaust gas pipe so voluminous space of the engine compartment is necessary.
It is an object of the present invention to provide an apparatus of EGR valve for an internal combustion engine to solve the above problems.
It is a further object of the present invention to provide an apparatus of EGR valve for an internal combustion engine in which the thermal effect on a plastic intake manifold due to high temperature of recirculating gas is prevented.
It is a further object of the present invention to provide an apparatus of EGR valve for an internal combustion engine in which the space in the engine compartment can be efficiently utilized.
In order to achieve the above objects of the present invention, an apparatus of Exhaust Gas Recirculation Valve comprises an intake manifold mounted on an outer wall of an engine cylinder head and having a first flange at one end of the intake manifold; and an exhaust gas recirculation valve for delivering exhaust gas discharged from a combustion chamber of the engine to the intake manifold; the exhaust gas recirculation valve attached on the first flange by an adapter having a second flange; wherein a gap is provided between a first border of the first flange and a second border of the adapter, thereby interrupting heat transfer, the first border facing to the adapter and the second border facing to the first border.
Further, the gap is evenly between the first border and the second border.
Furthermore, the gap has a depth by partial contact with the first flange and the second flange.
Further, the exhaust gas of combustion chamber is delivered to the Exhaust Gas Recirculation Valve through a passage formed in a cylinder head.